Vinyl resin - siloxane paint

ABSTRACT

A radiation-curable, film-forming paint binder is provided by mixing about 20 to about 80 parts by weight of (1) an alpha-beta olefinically unsaturated copolymer of vinyl monomers having molecular weight in the range of about 1,000 to about 25,000 and about 0.5 to about 5 units of alpha-beta olefinic unsaturation per 1,000 units molecular weight, and (2) an alpha-beta olefinically unsaturated siloxane containing about 3 to about 18 silicon atoms per molecule. The unsaturated siloxane is the reaction product of at least two molar parts of of a monomeric, monohydroxy ester of an alpha-beta olefinically unsaturated monocarbolylic acid, e.g., acrylates, methacrylates, crotonates, cinnamates, with one molar part of a siloxane wherein at least two silicon atoms have one valence satisfied by a hydroxyl group or an alkoxy group. Vinyl monomers may also be included in the paint dispersion.

United States Patent 1 Nordstrom 1 1 Jan. 30, 1973 [54] VINYL RESINSILOXANE PAINT [75] Inventor: John D. Nordstrom, Detroit, Mich. T'hammer-Donald Czala Assistant ExammerMelvyn 1. Marquis 1 Asslgneei 510"?Motor p y Dearbom, Attorney-John R. Faulkner and Olin B. Johnson 16 22Filed: Dec. 17, 1970 1 1 ABSTRACT 2 App], 99 246 A radiation-curable,film-forming paint binder is provided by mixing about 20 to about 80parts by weight Relaled Applicafilm Data of (1) an alpha-betaolefinically unsaturated [62] Division ofSer. No. 776,781, Nov. 18,1968, Pat. No. Y vinyl monomers having "mlecular 3,577,265, weight inthe range of about 1,000 to about 25,000 and about 0.5 to about 5 unitsof alpha-beta olefinic [52] U.S.C1. ..260/827,117/93.31,117/135.l,unsaturation per 1,000 units molecular weight, and 117/138.8 R, 117/148,204/159.l3, (2) an alpha-beta olefinically unsaturated siloxane204/159.l5, 260/33.6 SB, 260/41 B, containing about 3 to about 18silicon atoms per 260/465 UA molecule. The unsaturated siloxane is thereaction [51] Int. Cl ..C08f 35/02 product of at least two molar partsof of a monomeric, 1 Field 01 monohydroxy ester of an alpha-betaolefinically un- 204/l59-15 saturated monocarbolylic acid, e.g.,acrylates, methacrylates, crotonates, cinnamates, with one molar 1References Cited part of a siloxane wherein at least two silicon atomsUNTED STATES PATENTS have one valence satisfied by a hydroxyl group oran alkoxy group. Vinyl monomers may also be included 3,577,262 5/1971Nordstrom l l7/93.31 in the paint dispersion. 3,577,263 5/1971Nordstrom... 3,577,264 5/1971 Nordstrom ..117/93.31 14 Claims, N0Drawings VINYL RESIN SILOXANE PAINT This application is a division ofapplication Ser. No. 776,781 filed Nov. 18, 1968 now US. Pat. No.3,577,265.

This invention relates to the art of coating and is concerned with paintand painted articles of manufacture wherein the painted surface has highresistance to weathering. This invention is particularly concerned witharticles of manufacture having external surfaces of wood, metal orsynthetic polymeric solid coated with an in situ formed polymerizationproduct of a radiation-curable paint binder crosslinked on said surfaceby ionizing radiation and comprising a film-forming solution of analpha-beta olefinically unsaturated vinyl monomer-comprising binderresin and an alpha-beta olefinically unsaturated polysiloxane, thereaction product of one molar part siloxane having at least two hydroxyland/or hydrocarbonoxy groups and, preferably at least two molar partsof, a hydroxyl bearing ester of an alpha-beta unsaturated carboxylicacid. In a preferred embodiment, the film-forming solution also containsvinyl monomers.

In this application, the term paint is meant to include pigment and/orfinely ground filler, the binder without pigment and/or filler or havingvery little of the same, which can be tinted if desired. Thus, thebinder which is ultimately converted to a durable film resistant toweathering, can be all or virtually all that is used to form the film orit can be a vehicle for pigment and/or particulate filler material.

The siloxanes employed in the preparation of the binder have a reactivehydroxyl or hydrocarbonoxy group bonded to at least two of its siliconatoms. The term siloxane as employed herein refers to a compoundcontaining a APO-la I l linkage, with the remaining valences beingsatisfied by a hydrocarbon radical, a hydrocarbonoxy group, hydrogen, ahydroxyl group, or an oxygen atom which interconnects the silicon atomproviding such valence with another silicon atom.

A variety of methods are known to the art for preparing siloxanes. Theseinclude controlled hydrolysis of silanes, polymerization of a lowermolecular weight siloxane, reacting silicon tetrachloride with analcohol, etc. The preparation of siloxanes and their incorporation intoorganic resins is disclosed in US. Pat. Nos. 3,l54,597; 3,074,904;3,044,980; 3,044,979; 3,015,637; 2,996,479; 2,973,287; 2,937,230; and2,909,549.

The hydroxyl bearing ester is preferably a monohydroxy alkyl ester of analpha-beta olefinically unsaturated monocarboxylic acid. The preferredhydroxy esters are acrylates and methacrylates in that they provideolefinic unsaturation between the terminal carbon atoms and are readilypolymerizable at relatively low doses of ionizing radiation. A partialand exemplary list of such acrylates follows:

2-hydroxyethyl acrylate or methacrylate 2-hydroxypropyl acrylate ormethacrylate 2-hydroxybutyl acrylate or methacrylate 2-hydroxyoctylacrylate or methacrylate 2-hydroxydodecanyl acrylate or methacrylate2-hydroxy-3-chloropropyl acrylate or methacrylate2-hydroxy-3-acryloxypropyl acrylate or methacrylate2-hydroxy-3-methacryloxypropyl acrylate or methacrylate2-hydroxy-3-allyloxypropyl acrylate or methacrylate2-hydroxy-3-cinnamylpropyl acrylate or methacrylate2-hydroxy-3-phenoxypropyl acrylate or methacrylate2-hydroxy-3-(o-chlorophenoxy) propyl acrylate or methacrylate2-hydroxy-3-(p-chlor0phenoxy) propyl acrylate or methacrylate2-hydroxy-3-(2,4-dichlorophenoxy) propyl acrylate or methacrylate2-hydroxy-3-acetoxypropyl acrylate or methacrylate2-hydroxy-3-propionoxypropyl acrylate or methacrylate2-hydroxy-3-chloroacetoxypropyl acrylate or methacrylate2-hydroxy-3-dichloroacetoxypropyl acrylate or methacrylate2-hydroxy-3-trichloroacetoxypropyl acrylate or methacrylate acrylate orpropyl late 2-hydroxy-3-cinnamyloxypropyl acrylate or methacrylate3-acryloxy-2-hydroxypropyl acrylate or methacrylate3-allyloxy-2-hydroxypropyl acrylate or methacrylate3-chloro-2-hydroxypropyl acrylate or methacrylate3-crotonoxy-2-hydroxypropyl acrylate or methacrylate In addition toacrylate and methacrylates one may also use cinnamates, crotonates, etc.

The term ionizing radiation as employed herein means radiation havingsufficient energy to effect polymerization of the paint films hereindisclosed, i.e., energy equivalent to that of about 5,000 electron voltsor greater. The preferred method of curing films of the instant paintsupon substrates to which they have been applied is by subjecting suchfilms to a beam of polymerization effecting electrons having an averageenergy in the range of about 100,000 to about 500,000 electron volts.When using such a beam, it is preferred to employ a minimum of 25,000electron volts per inch of distance between the radiation emitter andthe workpiece where the intervening space is occupied by air. Adjustmentcan be made for the relative resistance of the intervening gas which ispreferably an oxygen-free inert gas such as nitrogen or helium. I preferto employ an electron beam which at its source of emission has averageenergy in the range of about 150,000 to about 500,000 electron volts.

The films formed from the paints of this invention are advantageouslycured at relatively low temperatures, e.g., between room temperature (20to 25C) and the temperature at which significant vaporization of itsmost volatile component is initiated, ordinarily between 20 and 70C. Theradiation energy is applied at dose rates of about 0.1 to about 100 Mradper second upon a preferably moving workpiece with the coating receivinga total dose in the range of about 0.5 to about 100, ordinarily betweenabout 1 and about 25, and most commonly between 5 and Mrad. The filmscan be converted by the electron beam into tenaciously bound, wear andweather resistant, coatings.

The abbreviation Mrad as employed herein means 1,000,000 Rad. The termRad as employed herein means that dose of radiation which results in theabsorption of 100 ergs of energy per gram of absorber, e.g., coatingfilm. The electron emitting means may be a linear electron acceleratorcapable of producing a direct current potential in the rangehereinbefore set forth. In such a device electrons are ordinarilyemitted from a hot filament and accelerated through a uniform voltagegradient. The electron beam, which may be about one-eighth inch indiameter at this point, is then scanned to make a fan-shaped beam andthen passed through a metal window, e.g., a magnesium-thorium alloy,aluminum, an alloy of aluminum and a minor amount of copper, etc., ofabout 0.003 inch thickness.

The term vinyl monomers as used herein refers to a monomeric compoundhaving a terminal group and excludes allylic compounds. The preferredvinyl monomers are esters of C to C monohydric alcohols and acrylic ormethacrylic acid, e.g., ethyl acrylate, ethyl methacrylate, butylacrylate, butyl methacrylate, octyl acrylate, 2-ethyl hexyl acrylate,etc. Alcohols of higher carbon number, e.g., C C can also be used toprepare such acrylates and methacrylates. Vinyl hydrocarbon monomers,e.g., styrene and alkylated styrenes such as vinyl toluene, alpha-methylstyrene, etc., may be used separately or in combination with acrylatesand methacrylates. Also in combination with acrylates and methacrylatesand/or vinyl hydrocarbon monomers, there may be used minor amounts ofother vinyl monomers such as nitriles, e.g.,

acrylonitrile, acrylamide, N-methylol acrylonitrile, vinyl halides,e.g., vinyl chloride, and vinyl carboxylates, e.g., vinyl acetate.

The alpha-beta olefinically unsaturated vinyl monomer comprising binderresins have a molecular weight above about 1,000 and below about 50,000,more commonly below about 25,000. In a preferred embodiment, such resinshave a molecular weight in the range of about 3,000 to about 10,000. Thevinyl monomer resins advantageously have about 0.5 to about 5,preferably about 1 to about 3.5, units of alphabeta olefinicunsaturation per 1,000 units molecular weight and can be prepared by avariety of methods.

In one embodiment, the vinyl monomer-comprising binder resin is thecopolymerization product of a minor proportion of glycidyl methacrylateand a major proportion of at least two vinyl monomers preferablyselected from the group consisting of styrene, esters of acrylic acid,and esters of methacrylic acid which is subsequently reacted withacrylic or methacrylic acid. Other vinyl hydrocarbons, e.g.,alpha-methyl styrene, vinyl toluene, etc., may be substituted for thestyrene. The initial copolymer may also contain minor amounts of acrylicacid and/or methacrylic acid.

In a second embodiment, the vinyl monomer-comprising binder resin isformed by reacting an unsaturated glycidyl ether with two or moredifferent vinyl monomers and reacting the resultantpolymer with anallylic alcohol.

In a third embodiment, the vinyl monomer-comprising binder resin isformed by reacting an allylic alcohol with two or more different vinylmonomers and reacting the resultant polymer with an allylic glycidylether.

The allylic alcohol used in the second and third embodiments isordinarily a C to C allylic alcohol, e.g., allyl alcohol,2-methyl-2-propen-l-ol, cinnamyl alcohol (3-phenyl-2-propen-1-ol),2-phenyl-2-propen-l-ol, etc. The aforementioned alcohols may have alkylsubstitution with resultant increase in the number of carbon atoms permolecule to as high as about 14.

The allylic glycidyl ethers used in the preparation of the aforesaidcopolymer are ordinarily a C to C glycidyl ether but will contain 17carbon atoms where the ether is formed from a C alcohol andepichlorohydrin. These include such compounds as allyl glycidyl ether,l-butene glycidyl ether and glycidyl ethers formed from theaforementioned allylic alcohols. Such ethers can be prepared by the wellknown reaction of such alcohols with epichlorohydrin or by theWilliamson Synthesis.

In a fourth embodiment, the vinyl monomer comprising binder resin is acopolymer of two or more vinyl monomers, including at least one hydroxylbearing constituent monomer, which has been reacted with an acyl halide.

In a fifth embodiment, the vinyl monomer comprising binder resin isformed by reacting a styrene-allyl alcohol copolymer with methacrylylchloride or acrylyl chloride.

in a sixth embodiment, the vinyl monomer comprising, binder resin isformed by reacting a partially hydrolyzed -polyvinylacetate,styrene-vinyl acetate copolymer, or ethylene-vinyl acetate copolymerwith methacrylyl chloride or acrylyl chloride.

It will be seen that in the aforedescribed embodiments, the vinylmonomer-comprising binder resin has a backbone or principalcarbon-to-carbon chain consisting essentially of vinyl monomers withside chains having terminal unsaturation. This olefinic unsaturationbetween the terminal carbons of the side chains is separated from theprincipal carbon-to-carbon chain by at least one ester linkage or etherlinkage.

The film-forming material should have an application viscosity lowenough to permit rapid application to the substrate in substantiallyeven depth and high enough so that at least 1 mil (.001 inch) film willhold upon a vertical surface without sagging. Such films will ordinarilybe applied to an average depth of about 0.1 to 4 mils with appropriateadjustment in viscosity and application technique. It will be obvious tothose skilled in the art that the choice of siloxane and of hydroxyesters in preparing the alpha-beta olefinically unsaturated siloxanecomponent of the binder solution can be varied so as to vary theviscosity of the siloxane component. The molecular weight of the vinylbinder resin may also be varied to control the viscosity of the bindersolution. Also, the type and quantity of vinyl monomers in the bindersolution are easily adjusted to provide a proper consistency forapplication by conventional paint application techniques, e.g.,spraying, roll coating, etc. It is also within the scope of thisinvention to employ the vinyl copolymer and the siloxane-unsaturatedresin product as the sole polymerizable materials in the binder. Wherenecessary for application viscosity a volatile solvent can be added andflashed off prior to curing.

Where the binder consists essentially of the alphabeta olefinicallyunsaturated vinyl monomer comprising binder resin and the alpha-betaolefinically unsaturated polysiloxane, the binder contains about 20 toabout 80, advantageously about 30 to about 70, parts by weight of thevinyl binder resin and about 20 to about 80, advantageously about 30 toabout 80, parts by weight of the siloxane.

Where the binder contains significant amounts of vinyl monomers, thebinder will advantageously contain about to about 200, preferably aboutto about 100, parts by weight vinyl monomers and a resinous componentthat comprises about 20 to 80, preferably about 30 to 70, parts byweight of the vinyl resin and about 20 to 80, preferably about 30 toabout 70, parts by weight of the siloxane. Minor amounts of otherpolymerizable monomers, e.g., allylic compounds, may be used to make upthe balance, if any. This invention is particularly concerned with thosecoating wherein the film-forming solution, exclusive of vinyl monomers,consists essentially of the vinyl monomer-comprising binder resin andthe siloxane-unsaturated ester product, herein defined to mean coatingcompositions wherein these components constitute at least 85 wt. percentof the film-forming binder.

This invention will be more fully understood from the followinillustrative examples:

EXAMPLE 1 A siloxane-unsaturated ester and vinyl monomercomprising paintis prepared from the following components in the manner hereinafter setforth:

a. Preparation of the Siloxane Component Reactants Parts by weightMethoxy functional acyclic siloxane" l78 Hydroxyethyl methacrylate 1 l8Tetraisopropyl titanate 0.32 Hydroquinone 0.06

(l) a commercially available methoxylated partial hydrolysate ofmonophenyl and phenylmethyl silanes (largely condenseddimethyltriphenyltrimethoxysiloxane) and has the following typicalproperties:

average molecular weight 750 850 average number of silicon atoms permolecule 5 6 average number of methoxy groups per molecule 3 4 Thesiloxane, the methacrylate monomer and hydroquinone polymerizationinhibitor are heated to C in a flask fitted with a Barrett typedistillation receiver. The titanate catalyst is added and thetemperature is raised to C over a three hour period during which timemethanol is removed by distillation. The cooled reaction product has aviscosity of 0.6 stoke at 25C.

b. Preparation of the Vinyl Monomer-Comprising Binder Resin StartingMaterials Parts by weight lene 600 Methyl methacrylate 196 Ethylacrylate 333 Glycidyl methacrylate 7l Azobisiso butyronitrile 6Hydroquinone 0.12

Methacrylic acid 42 Triethyl amine 0.96

Procedure The reaction solvent, xylene, is charged to a flask fittedwith a stirring rod, an addition funnel, a thermometer, a nitrogen inlettube and a condenser. The amount of xylene is equal to the total weightof vinyl monomers to be added. The xylene is heated to reflux, nitrogenis bubbled through the solution during heat up and throughout thereaction. The combined monomers and initiator (Azobisiso Butyronitrile)is added to the refluxing solution evenly over a two-hour period. Theinitiator weight is 10 parts by weight per 1,000 parts by weight ofvinyl monomers. The reaction solution is refluxed until the conversionof monomer to polymer is greater than 97 percent (8 16 hours).

In the second step. hydroquinone is added as an inhibitor and thenmethacrylic acid is added to react with the residual epoxy groups on thepolymer. Triethyl amine is used as a catalyst. This esterificationreaction is carried out at reflux temperatures until 80 percentesterification is accomplished (determined by residual acid number). Thexylene is then removed by vacuum distillation and the polymer dissolvedin methyl methacrylate so that the weight ratio of polymer to solvent is2.

c. Preparation of the Paint Components Parts by weight Siloxane-esterproduct of (a) above l0 Acixllic resin of (b) above 15 Me y]methacrylate 2.5

270 KV 25 ma Electron beam potential Electron beam current Dose MradAtmosphere nitrogen Distance, workpiece to emitter 10 inches EXAM PLE 2The procedure of Example 1 is repeated except that the vinylmonomer-comprising polymer is prepared from the following ingredients inthe following manner:

Parts by weight Ethyl acrylate 38.8 Methyl methacrylate 23.2 Allylglycidyl ether 37.0 Benzoyl Peroxide 1.0 Xylene solvent To a reactionvessel provided with a condenser, thermometer, agitator, and droppingfunnel there are charged an amount of xylene equal in weight to thereactants to be added in the first reaction step. The xylene is heatedto about 100 120 C. The four reactants are thoroughly mixed and addedslowly with a dropping funnel to the heated xylene over a period of fourhours. The reaction is held at this temperature for 1 2 hours afteraddition is complete and then allowed to cool to room temperature.

A binder polymer is formed in a second reaction step from the followingmaterials:

Parts by weight Copolymer from Step 1 69.4 Allyl Alcohol 30.4 PotassiumHydroxide 0.2

A solution of the allyl-alcohol and potassium hydroxide is added to thecopolymer at room temperature. The mixture is then heated to atemperature of 100 120C. This temperature is maintained for about 7hours and allowed to cool. The binder polymer reaction mixture is heatedto about 60C and the xylene and excess reactant are removed by vacuumdistillation.

At a temperature of about 60C styrene and hydroquinone are added to thepolymer to form a filmforming solution having the following composition:

Parts by weight Polymer from Step 11 66.66

Styrene 33.27 Hydroquinone 0.07

EXAMPLE 3 The procedure of Example 1 is repeated except that the vinylmonomer-comprising polymer is prepared from the following ingredients inthe following manner:

Parts by weight Ethyl acrylate 39 Methyl methacrylate 24 Allyl alcohol36 Benzoyl peroxide 1 Xylene solvent To a reaction vessel provided witha condenser, thermometer, agitator, and dropping funnel there arecharged an amount of xylene equal in weight to the reactants to be addedin the first reaction step. The xylene is heated to about 100 120C. Thefour reacting materials are thoroughly mixed and added slowly with adropping funnel to the heated xylene over a period of 4 hours. Thereaction is held at this temperature for 1 2 hours after addition iscomplete and then allowed to cool to room temperature.

A binder polymer is formed in a second reaction step from the followingmaterials:

Parts by weight Copolymer from Step 1 69 Allyl glycidyl ether 30.8Potassium hydroxide 0.2

A solution of the allyl glycidyl ether and potassium 0 hydroxide isadded to the copolymer at room temperature. The mixture is then heatedto a temperature of C. This temperature is maintained for about 7 hoursand allowed to cool. The binder polymer reaction mixture is heated toabout 60C and the xylene and excess reactant are removed by vacuumdistillation.

At a temperature of about 60C styrene and hydroquinone are added to thepolymer to form a filmforming solution having the following composition:

Parts by weight Polymer from Step 11 67 Styrene 32.93 Hydroquinone 0.07

EXAMPLE 4 The procedure of Example 1 is repeated except that the vinylmonomer-comprising polymer is prepared from the following ingredients inthe following manner:

Step 1. I

Reactants Parts by weight Methyl methacrylate 400 Ethyl acrylate 400Hydroxy ethyl methacrylate 195 Toluene 1000 Benzoyl peroxide 30 Thebenzoyl peroxide is dissolved in a solution of the methyl methacrylate,ethyl acrylate, and hydroxy-ethyl methacrylate and one-half of thetoluene. This solution is added incrementally to the remainder of thetoluene at reflux over a 7-hour period with a final pot temperature ofabout 138 140C. Reflux is maintained for another 3 hours and thesolution cooled.

Step 11 Reactants Parts by weight Solution from Step 1 Y 500 Acrylylchloride 33.8 Toluene 30 EXAMPLE 5 The procedure of Example 1 isrepeated except that the vinyl monomer-comprising polymer is preparedfrom the following ingredients in the following manner:

An electron-polymerizable paint is prepared from the following materialsin the manner hereinafter set forth: 100 parts by weight of astyrene-allyl alcohol copolymer containing 21.4 weight percent allylalcohol and having an average molecular weight of about 1,620

and 0.1 part by weight hydroquinone are dissolved in toluene and heatedto 90C. and 41.8 parts by weight of methacrylyl chloride in tolueneadded dropwise over a 1-hour period. Heating is continued and thetemperature allowed to rise to toluene reflux until essentially completecessation of gas liberation is obtained after an additional 5 hours.Infrared analysis shows about percent residual hydroxyl. The solvent isremoved at the water pump.

EXAMPLE 6 The procedure of Example 1 is repeated except that the vinylmonomer-comprising polymer is prepared from the following ingredients inthe following manner:

Two hundred and fifty parts by weight of a 25 percent nonvolatilessolution of solution polymerized polyvinylacetate supplied in a blend ofabut 85 percent toluene and percent methanol are placed in a 1 literflask equipped for distillation, agitation and dropwise solventaddition. The polyvinylacetate is hydrolyzed to contain about 3.5percent hydroxyl. Methanol is removed as the toluene azeotrope andadditional toluene added to maintain volume. After completion ofmethanol removal, the solution is maintained at reflux and 16 parts byweight of methacrylyl chloride in parts by weight of dry dioxane addeddropwise over one-half hour. Heating is continued for an additional 4hours. Toluene is added during distillation and the excess acid chlorideand excess toluene are removed at the water pump. The resultant resin isrecovered.

EXAMPLE 7 The procedure of Examples 1 6 are repeated except for thedifference that the vinyl monomer content of the paint binder solutionis a mixture of styrene and methyl methacrylate and constitutes about 10weight percent of said solution.

EXAMPLE 8 The procedure of Examples 1 6 are repeated except for thedifference that the vinyl monomer content of the paint binder solutionis a mixture of methyl methacrylate, butyl acrylate and 2-ethyl hexylacrylate and constitutes about 60 weight percent of said solution.

EXAMPLE 9 The procedure of Examples 1 6 are repeated except for thedifference that the vinyl monomer content of the paint binder solutionis a mixture of ethyl acrylate, butyl methacrylate and octyl acrylateand constitutes about weight percent of said solution.

EXAMPLE 10 The procedure of Examples 1 6 are repeated except for thedifference that the vinyl monomer content of the paint binder solutionis a mixture of styrene and vinyl toluene and constitutes about 50weight percent of said solution.

EXAMPLE 11 The procedure of Examples l 6 are repeated except that thealpha-beta olefinically unsaturated siloxane content is adjusted toconstitute weight percent of the paint binder solution and thealpha-beta olefinically unsaturated, vinyl monomer-comprising binderresin content is adjusted to constitute weight percent of said bindersolution exclusive of vinyl monomers.

EXAMPLE 12 EXAMPLE 13 The procedure of the preceding examples isrepeated except that the alpha-beta olefinically unsaturated siloxane isprepared from the following components in the following manner:

Reactants Parts by weight Hydroxy functional cyclic siloxane" 200Hydroxyethyl methacrylate 71 Hydroquinone 0.1

Xylene, solvent l 16 (1) a commercially available hydroxy functional,cyclic polysiloxane having the following typical properties:

Hydroxy content, Dean Stark percent condensible 5.5 percent free 0.5Average molecular weight 1600 Combining weight 400 Refractive index1.531 to 1.539

Softening point, Durrans Mercury Method, degrees F. 200

At 60% solids in Xylene Specific Gravity at 77F 1.075 Viscosity at 77F,centipoises 33 Gardner-Holdt A 1 Procedure A three neck flask fittedwith a stirring meter, a thermometer, a nitrogen inlet and a Barretttrap is charged with the siloxane, the methacrylate, the xylene and thehydroquinone. This solution is heated to reflux, 138C, over a 30 minuteperiod. Nitrogen is bubbled into the reaction throughout the wholeprocedure. By-product water is slowly removed and the temperaturegradually rises to 146C. After 5 hours, 8.5 ml of water is collectedindicating nearly complete reaction. The xylene is removed by reducedpressure distillation and the product is then diluted to 70 percentnon-volatile content with methyl methacrylate.

EXAMPLE 14 The procedure of Example 1 is repeated except that thepolysiloxane employed to produce the alpha-beta oleflnically unsaturatedsiloxane is a methoxylated partial hydrolysate of monophenyl andphenylmethyl silanes consisting essentially ofdimethyltriphenyltrimethoxytrisiloxane and has the following typicalproperties:

Average molecular weight 470 Combining Weight Specific gravity at 77F1.105 Viscosity at 77F, centistokes l3 EXAMPLE 15 The procedure ofExample 1 is repeated except that the polysiloxane employed to producethe alpha-beta olefinically unsaturated siloxane isdipropoxytetramethylcyclotrisiloxane.

EXAMPLE16 The procedure of Example 1 is repeated except that thepolysiloxane employed to produce the alpha-beta olefinically unsaturatedsiloxane is dibutoxytetramethyldisiloxane.

EXAMPLE 17 The procedure of Example 1 is repeated except that thepolysiloxane employed to produce the alpha-beta olefinically unsaturatedsiloxane is pentamethyltrimethoxytrisiloxane.

EXAMPLE 18 The procedures of Examples 1, 13 and 14 are repeated exceptthat an equivalent amount of 2-hydroxyethyl acrylate is substituted forthe hydroxyethyl methacrylate in preparing the siloxane-unsaturatedester product.

EXAMPLE 19 The procedures of Examples 1, 13 and 14 are repeated exceptthat an equivalent amount of 2-hydroxypropyl methacrylate is substitutedfor the hydroxyethyl methacrylate in preparing the siloxane-unsaturatedester product.

EXAMPLE 20 The procedures of Examples 1, l3 and 14 are repeated exceptthat an equivalent amount of 2-hydroxybutyl acrylate is substituted forthe hydroxyethyl methacrylate in preparing the siloxane-unsaturatedester product.

EXAMPLE 21 EXAMPLE 22 The procedures of Examples 1, l3 and 14 arerepeated except that an equivalent'amount of 2-hydroxydodecanylmethacrylate is substituted for the hydroxyethyl methacrylate inpreparing the siloxane-unsaturated ester product.

EXAMPLE 23 The procedures of Examples 1, l3 and 14 are repeated exceptthat an equivalent amount of 3-chloro-2- hydroxypropyl acrylate issubstituted for the hydroxyethylmethacrylate in preparing thesiloxane-unsaturated ester product.

EXAMPLE 24 The procedures of Examples 1, l3 and 14 are repeated exceptthat an equivalent amount of 3-acryloxy- 2-h ydroxypropyl methacrylateis substituted for the hydroxyethyl methacrylate in preparing thesiloxaneunsaturated ester product.

EXAMPLE 25 The procedures of Examples 1, 13 and 14 are repeated exceptthat an equivalent amount of 3- crotonoxy-Z-hydroxypropyl acrylate issubstituted for the hydroxyethyl methacrylate in preparing thesiloxane-unsaturated ester product.

EXAMPLE 26 The procedures of Examples 1, 13 and 14 are repeated exceptthat an equivalent amount of 3-acryloxy- Z-hydroxypropyl cinnamate issubstituted for the hydroxyethyl methacrylate in preparing thesiloxaneunsaturated ester product.

EXAMPLE 27 The procedures of Examples 1, 13 and 14 are repeated exceptthat an equivalent amount of 3-acryloxy- 2-hydroxypropy1 crotonate issubstituted for the hydroxyethyl methacrylate in preparing thesiloxaneunsaturated ester product.

EXAMPLE 28 The procedures of Examples 18 27 are repeated using an amountof the monohydroxy ester of an alphabeta olefinically unsaturatedmonocarboxylic acid that is sufficient to react with at least onehydroxy or hydrocarbonoxy functional group of such siloxane butinsufficient to react with all of the functional groups of the siloxanemolecules in the reaction mixture.

EXAMPLE 29 The procedures of Examples 18 27 are repeated using an amountof the monohydroxy ester of an alphabeta olefinically unsaturatedmonocarboxylic acid that is in excess of the amount required to satisfyall of the hydroxy and hydrocarbonoxy functional groups of the siloxanemolecules in the reaction mixture.

EXAMPLE 30 A pigmented pain is prepared by premixing parts by weight ofthe siloxane-unsaturated ester product of Example 13 with parts byweight of commercial grade titanium dioxide pigment and 20 parts byweight of methyl methacrylate. The mixture is ground by shaking with anequal amount of glass beads in a conventional paint shaker for 30minutes. The premix is diluted with an additional 75 parts by weight ofthe siloxane-unsaturated ester product and 65 parts by weight of theresultant mix are diluted with 35 parts by weight of an equimolarmixture of styrene and methyl methacrylate. This mix is added to 35parts methyl methacrylate and 65 parts by weight of the acrylic resin ofExample 1. The paint is applied to metal, wood and polymeric (ABSacrylonitrilebutadienestyrene copolymer) substrates to an average depthof about 1.5 mils and cured thereon with an electron beam in the mannerof the previous examples.

EXAMPLE 31 The procedure of Example 1 is repeated except that curing iseffected with the beam potential of 175,000

volts with the workpiece 3 inches from the emitter and at 400,000 voltsat inches each being in a nitrogen atmosphere containing minor amountsof carbon dioxide.

EXAMPLE 32 The procedures of Examples 1, l3, and 14 are repeated exceptthat the alpha-beta olefinically unsaturated copolymer and thealpha-beta olefinically unsaturated siloxane are employed in the absenceof vinyl monomers by reducing the viscosity to spraying consistency withtoluene which is flashed off prior to curmg.

EXAMPLE 33 Paints are prepared by admixing 160 parts by weight of thesiloxane-unsaturated ester product of Example 1 and 160 parts by weightof the vinyl copolymer of Example l, dividing this mix into two equalparts, and diluting one such part with 100 parts by weight methylmethacrylate and the other part with 200 parts by weight methylmethacrylate. The resultant film-forming solutions are applied to metalsubstrates and crosslinked thereon with an electron beam in the mannerof the preceding examples.

EXAMPLE 34 Paints are prepared by admixing 40 parts by weight of thesiloxane-unsaturated ester product of Example 13 and 40 parts by weightof the vinyl copolymer of Example 2, dividing this mix into equal parts,and diluting one such part with 10 parts by weight methyl methacrylateand the other part with parts by weight methyl methacrylate. Theresultant film-forming solutions are applied to metal substrates andcrosslinked thereon with an electron beam in the manner of the precedingexamples.

The term copolymer of vinyl monomers is herein defined to mean a polymerwherein a major amount (above 50 wt. percent) of the constituentmonomers therein are selected from two or more vinyl monomers.

A variety of suitable si loxanes for use in this invention are describedand illustrated in detail in my parent copending application Ser. No.776;78l filed Nov. 18, 1968 now US. Pat. No. 3,577,265 and thedisclosures thereof are incorporated herein by reference.

It will be understood by those skilled in the art that modifications canbe made within the foregoing examples within the scope of the inventionas hereinafter claimed.

I claim:

1. A radiation-curable pain which on a pigment and particulatefiller-free basis consists essentially of 1. about 20 to about 80 partsby weight of an alphabeta olefinically unsaturated copolymer of vinylmonomers having molecular weight in the range of about 1,000 to about25,000 and about 0.5 to about 5 units of alpha-beta olefinicunsaturation per 1,000 units molecular weight, and

2. about 80 to about 20 parts by weight of an alphabeta olefinicallyunsaturated siloxane formed by reacting at etherification reactiontemperature at least two molar parts of a monomeric, monohydroxy esterof an alpha-beta olefinically unsaturated monocarboxylic acid with onemolar part of a Si:, Si siloxane wherein at least two silicon atomsthereof have one valence satisfied by a functional group selected fromthe group consisting of hydroxyl groups and C C alkoxy groups, theremaining valences of the silicon atoms of said siloxane being satisfiedby oxygen radical, hydrocarbon radical, hydrocarbonoxy radical, hydrogenradical or hydroxyl radical.

2. A radiation-curable pain in accordance with claim 1 wherein saidmonohydroxy ester of an alpha-beta olefinically unsaturatedmonocarboxylic acid is an ester of acrylic or methacrylic acid and a C Cdihydric alcohol.

3. A radiation-curable paint in accordance with claim 1 wherein saidmonohydroxy ester of an alphabeta olefinically unsaturatedmonocarboxylic acid is an ester of crotonic acid and a C C dihydricalcohol.

4. A radiation-curable paint in accordance with claim 1 wherein saidmonohydroxy ester of an alphabeta olefinically unsaturatedmonocarboxylic acid is an ester of cinnamic acid and a C C dihydricalcohol.

5. A radiation-curable paint in accordance with claim 1 wherein saidsiloxane is a Si Si siloxane.

6. A radiation-curable paint in accordance with claim 1 wherein saidalkoxy group is a methoxy group.

7. A radiation-curable paint in accordance with claim 1 wherein saidresin has between about 0.5 and about 3.5 units of alpha-beta olefinicunsaturation per 1,000 units molecular weight.

8. A radiation-curable paint in accordance with claim 1 wherein saidresin has between about 1 and about 3.5 units of alpha-beta olefinicunsaturation per 1,000 units molecular weight.

9. A radiation-curable paint which on a pigment and particulatefiller-free basis consists essentially of I. about 10 to about 200 partsby weight vinyl monomers which are selected from esters of acrylic ormethacrylic acid and a C C monohydric alcohol and C C vinylhydrocarbons,

. about 30 to about parts by weight of an alphabeta olefinicallyunsaturated copolymer of vinyl monomers having molecular weight in therange of about l,000 to about 25,000 and between 0.5 and 5 unitsmolecular weight, and

3. about to about 20 parts by weight of an alphabeta olefinicallyunsaturated siloxane formed by reacting at etherification reactiontemperature at least two molar parts of a monomeric, monohydroxy esterof an alpha-beta olefinically unsaturated monocarboxylic acid with onemolar part of a Si Si siloxane wherein at least two silicon atomsthereof have one valence satisfied by functional groups selected fromthe group consisting of hydroxyl groups and C, C alkoxy groups, theremaining valences of the silicon atoms of said siloxane being satisfiedby oxygen radical, hydrocarbonoxy radical, hydrocarbon radical, hydrogenradical, or hydroxyl radical.

10. A radiation-curable paint in accordance with claim 9 wherein saidresin has between about 1 and about 3.5 units of alpha-beta olefinicunsaturation per 1,000 units molecular weight.

11. A radiation-curable paint in accordance with claim 9 wherein saidmonohydroxy ester of an alpha- 13. A radiation-curable paint inaccordance with claim 9 wherein said monohydroxy ester of an alphabetaolefinically unsaturated monocarboxylic acid is an ester of cinnamicacid and a C, C dihydric alcohol.

14. A radiation-curable paint in accordance with claim 9 wherein saidalkoxy group is a methoxy group.

1. A radiation-curable pain which on a pigment and particulatefiller-free basis consists essentially of
 1. about 20 to about 80 partsby weight of an alpha-beta olefinically unsaturated copolymer of vinylmonomers having molecular weight in the range of about 1,000 to about25,000 and about 0.5 to about 5 units of alpha-beta olefinicunsaturation per 1,000 units molecular weight, and
 1. about 10 to about200 parts by weight vinyl monomers which are selected from esters ofacrylic or methacrylic acid and a C1 - C8 monohydric alcohol and C8 - C9vinyl hydrocarbons,
 2. about 30 to about 70 parts by weight of analpha-beta olefinically unsaturated copolymer of vinyl monomers havingmolecular weight in the range of about 1,000 to about 25,000 and between0.5 and 5 units molecular weight, and
 2. about 80 to about 20 parts byweight of an alpha-beta olefinically unsaturated siloxane formed byreacting at etherification reaction temperature at least two molar partsof a monomeric, monohydroxy ester of an alpha-beta olefinicallyunsaturated monocarboxylic acid with one molar part of a Si3 -Si18siloxane wherein at least two silicon atoms thereof have one valencesatisfied by a functional group selected from the group consisting ofhydroxyl groups and C1 - C4 alkoxy groups, the remaining valences of thesilicon atoms of said siloxane being satisfied by oxygen radical,hydrocarbon radical, hydrocarbonoxy radical, hydrogen radical orhydroxyl radical.
 2. A radiation-curable pain in accordance with claim 1wherein said monohydroxy ester of an alpha-beta olefinically unsaturatedmonocarboxylic acid is an ester of acrylic or methacrylic acid and aC2 - C8 dihydric alcohol.
 3. A radiation-curable paint in accordancewith claim 1 wherein said monohydroxy ester of an alpha-betaolefinically unsaturated monocarboxylic acid is an ester of crotonicacid and a C2 - C8 dihydric alcohol.
 3. about 80 to about 20 parts byweight of an alpha-beta olefinically unsaturated siloxane formed byreacting at etherification reaction temperature at least two molar partsof a monomeric, monohydroxy ester of an alpha-beta olefinicallyunsaturated monocarboxylic acid with one molar part of a Si3 -Si18siloxane wherein at least two silicon atoms thereof have one valencesatisfied by functional groups selected from the group consisting ofhydroxyl groups and C1 - C4 alkoxy groups, the remaining valences of thesilicon atoms of said siloxane being satisfied by oxygen radical,hydrocarbonoxy radical, hydrocarbon radical, hydrogen radical, orhydroxyl radical.
 4. A radiation-curable paint in accordance with claim1 wherein said monohydroxy ester of an alpha-beta olefinicallyunsaturated monocarboxylic acid is an ester of cinnamic acid and a C2 -C8 dihydric alcohol.
 5. A radiation-curable paint in accordance withclaim 1 wherein said siloxane is a Si3 - Si12 siloxane.
 6. Aradiation-curable paint in accordance with claim 1 wherein said alkoxygroup is a methoxy group.
 7. A radiation-curable paint in accordancewith claim 1 wherein said resin has between about 0.5 and about 3.5units of alpha-beta olefinic unsaturation per 1,000 units molecularweight.
 8. A radiation-curable paint in accordance with claim 1 whereinsaid resin has between about 1 and about 3.5 units of alpha-betaolefinic unsaturation per 1,000 units molecular weight.
 9. Aradiation-curable paint which on a pigment and particulate filler-freebasis consists essentially of
 10. A radiation-curable paint inaccordance with claim 9 wherein said resin has between about 1 and about3.5 units of alpha-beta olefinic unsaturation per 1,000 units molecularweight.
 11. A radiation-curable paint in accordance with claim 9 whereinsaid monohydroxy ester of an alpha-beta olefinically unsaturatedmonocarboxylic acid is an ester of acrylic methacrylic acid and a C2 -C8 dihydric alcohol.
 12. A radiation-curable paint in accordance withclaim 9 wherein said monohydroxy ester of an alpha-beta olefinicallyunsaturated monocarboxylic acid is an ester of crotonic and a C2 - C8dihydric alcohol.
 13. A radiation-curable paint in accordance with claim9 wherein said monohydroxy ester of an alpha-beta olefinicallyunsaturated monocarboxylic acid is an ester of cinnamic acid and a C2 -C8 dihydric alcohol.